The present invention relates to an open-end spinning rotor. EP 0 090 939 A2discloses a method by which a collar is pressed on a shaft, is pressed against the spinning rotor, and is attached by means of a conical spring washer. DE-OS 28 12 297 discloses an open-end spinning rotor made in one piece with a hub and connected to the shaft through shrink-fitting of the hub on the shaft. DE-A 29 39 325 describes a rotor which is separably joined to a collar by means of hooks. DE-A 40 20 518 discloses a rotor shaft which is made in one piece with a collar, with the spinning rotor being attached to the shaft in that the latter bears upon the collar and is pressed by means of a conical spring washer against the collar.
Open-end spinning rotors are operated at rotational speeds exceeding 100,000 RPM. The most stringent specifications are required for the attachment of the spinning rotor since it is under great stress because of mechanical oscillations. At the same time, operation at such high rotational speed requires, because of the known technical problems of oscillation, that the axial projection of the spinning rotor to its nearest bearing point, i.e. a pair of bearing disks, should be as short as possible. This necessity requires that the axial length of the collar must be kept to a minimum, and this has the disadvantage with pressed-on collars that less surface is available, resulting in the danger that the connection between the power and shaft may open up during operation. If the rotor shaft and the collar are made in one piece this disadvantage can be avoided, but an open-end spinning rotor designed in this manner can only be manufactured at great cost. It is a further disadvantage that the shaft is not universally suited for utilization both with a thick-walled and a thin-walled spinning rotor, so that the collar must be ground to balance the spinning rotor. When a spinning rotor is being replaced, the hub cannot be replaced at the same time, and this has as a consequence that the newly installed spinning rotor, together with the shaft which is used again, is very difficult to balance again.